In human-computer interaction research and practice, policy concerns can sometimes fall to the margins, orbiting at the periphery of the traditionally core interests of design and practice. This perspective ignores the important ways that policy is bound up with the technical and behavioral elements of the HCI universe. Policy concerns are triggered as a matter of course in social computing, CSCW, systems engineering, UX, and related contexts because technological design, social practice and policy are dynamically entangled and mutually constitutive. Through this research, we demonstrate the value of a stronger emphasis on policy in HCI by exploring a recent controversy on Reddit: "AMAgeddon." Applying Hirschman's exit, voice and loyalty framework, we argue that the sustainability of online communities like Reddit will require successful navigation of the complex and often murky intersections among technical design and human interaction through a distributed participatory policymaking process that promotes user loyalty.

The traditional core of CSCW focuses on the relationships, tensions, and gaps between technical systems and social activity. Policy orbits around this core as a persistent but marginally represented presence. In the last few years, however, CSCW has witnessed an upsurge of interest in (re)integrating policy more explicitly and meaningfully into research and practice. For example, recent scholarship stressed the mutually constitutive and interconnected threads of design, practice, and policy [31]. This paper expands upon those motivations through a qualitative case study of the role of policy in library mass digitization work and the subsequent emergence and evolution of the HathiTrust cooperative partnership. By tracing the origins and impacts of early policy decisions in this context, this research contributes to understandings of how and why policy can both close and open spaces of social practice and technical design, functioning as a source of embedded generativity in complex sociotechnical systems.